Conventional row-crop planters, whether designed for conventional tillage, minimum tillage, or no tillage, are commonly equipped with forming bars or openers which scrape along the surface of the soil to form an open trough for receiving seeds deposited by a suitable seed-metering mechanism. A coulter in the form of a fluted or rippled cutting wheel may be used to slice through trash and soil ahead of the opener so that the opener is better able to form a firm trench for receiving the seeds. One or more press wheels are also commonly provided to press the seed firmly into the soil, and usually to close the soil around the seed, for the purpose of obtaining better germination and emergence.
An object of this invention is to provide a planter which maximizes emergence with a minimum amount of tillage, thereby producing results superior to those of presently available minimum tillage planters while at the same time reducing energy consumption, erosion problems, and compaction problems. Another object is to provide a planter particularly suitable for use with an undercutter plow so that seeds are planted at prescribed intervals behind the plow without the formation of exposed trenches or furrows in the soil. A still further object is to provide a system in which seeds are delivered directly to their planting sites beneath the surface of the soil, immediately following, and as part of, an undercutter plowing operation. An additional object is to provide means for firming the soil along the lower portion of the tunnel or closed furrow, just prior to seed placement within that closed furrow, along with means for firming the soil above and to the side of each seed immediately after placement.
In brief, the apparatus takes the form of a downwardly and rearwardly sloping seed delivery member hingedly connected to the trailing portion of an undercutter blade and equipped with a gage wheel assembly that rides over the surface of the soil to support the free rear end of the seed delivery member at the desired sub-surface elevation, and also to press or firm the soil following seed application. An air metering system is provided to supply seeds to the tubular member at a predetermined frequency. The seeds are carried downwardly and rearwardly through the tubular rear portion of the member by a stream of air until the seeds approach the discharge opening at the member's trailing or distal end, at which point much of the air is vented and the seeds continue the remainder of the way by reason of momentum and residual air flow. Firming of the soil along the lower portion of the sub-surface tunnel or furrow is achieved because of the downward and rearward slope of the seed delivery member and because of the longitudinal keel or flange provided at its distal end. The gage wheel assembly is connected directly to the trailing distal end of the tubular member and rides upon the surface of the soil to perform the dual functions of maintaining the discharge opening at a selected depth beneath the surface and of firming the soil about the seeds immediately after they are planted.
At its proximal or forward end, the delivery tube or member is connected to a double-acting hinge which is in turn secured to the undercutter blade assembly. The hinge allows vertical movement of the member's trailing end relative to the undercutter blade, thereby permitting the seeds to be discharged at a depth controlled by the rear gage wheel assembly rather than by the depth of the undercutter blade spaced in front of that assembly. Horizontal movement of the member's trailing end is also permitted by the double hinge connection, thus insuring proper tracking when the planter is left in the ground while turning corners.
Auxiliary tubes may be provided at the trailing or distal end of the seed delivery member for injecting liquid or granular insecticides, fungicides, and the like into the tunnel-like furrow along with each seed discharged from the delivery tube. If desired, a fertilizer discharge tube may also be provided, preferably forward or to the side of the seed discharge opening of the seed delivery member, for supplying fertilizer to the soil around the seed bed as it is later formed by that member.
Other objects, features, and advantages will be apparent from the specification and drawings.